Oh thank you so much once again for your precious advices. Well about your questions:
Will your story and game mechanics be enhanced by the eroge angle?
Probably yes or probably doesn't, but I just know I have to try it.
Will the eroge be enhanced by the story and game mechanics?
I dont think so, in case of game mechanics I'm not super expert, that's why after trying Renpy I'm looking for something else. I've heard about kengine but it still under development, I mean, it's not available. So I have to find out the best engine for my game, but also easy to use.
Can you pull off the eroge angle visually?
Well, I have few ideas about that. It can be explicit but at the same time a bit more artistic, for sure I don't wanna do something usual